The present invention relates generally to control switches and, more particularly, to a contactless control switch that includes a shielded vane therein to provide magnetic shielding to a magnetic sensor of the switch.
Electrical switches are used as control switches for a variety of applications in various industries, with one such example being in specialty vehicle markets—such as heavy trucks, agricultural equipment, and construction equipment, for example—where the switches are employed to control the motor vehicle lighting, the windshield wipers, the rear windshield heating, the cruise control functions, the internal central locking and other functions on and off. Often the control switches are in the form of rocker switches that may be pushed by an operator to rotate/tilt from a neutral position (i.e., switched-off state) to one or more activated positions (i.e., a switched-on state) that control operation of an associated system/component, although control switches may also be constructed as pushbutton switches or toggle switches as other examples.
One type of common control switch is a contactless switch that operates by moving a magnet past a fixed magnetic sensor, such as a Hall effect IC or a magnetoresistive sensor, in order to control and determine the functions/modes provided by the switch. With respect to contactless control switches that are utilized for one of various applications, it is recognized that existing designs of such switches can limit the performance thereof. For example, existing contactless control switches constructions may suffer from issues regarding the ability of the magnetic sensors to detect the magnetic field with sufficient strength, such that discerning a distinct switching position may be difficult. This problem of correctly discerning a distinct switching position may be further compounded if the switch is not constructed in a fashion that provides the magnetic sensors with sufficient protection from external magnetic fields, as the presence of such external magnetic fields interferes with the ability of the magnetic sensors to attribute a sensed magnetic field to the switch magnets.
To provide protection from external magnetic fields, some prior art contactless control switches implement a shielding housing that completely surrounds the switch in order to block the external magnetic fields from the magnetic sensors therein. While such shielding housings may be effective in providing magnetic shielding, it is recognized that the housing can be bulky and increase the size of the switch. Such shielding housings can also increase the overall cost of the switch, as they necessitate the addition of an entirely separate/additional component to the switch.
It would therefore be desirable to provide a contactless control switch that is resistant to the influence from external magnetic fields. It would further be desirable for such a contactless control switch to be provided with such external magnetic field shielding without requiring the addition of a dedicated/separate shielding housing.